Removal of volatile organic pollutants from drinking water

ABSTRACT

Volatile, toxic organic pollutants are removed from drinking water by partially filling a container with water and drawing a vacuum in the space above the water so that the pollutants exit the water into the space above the water for subsequent dispersement into the atmosphere.

This application is a continuation in part of pending application Ser. No. 894,941 filed Jun. 8, 1992 (now abandoned) which is a continuation in part of application Ser. No. 693,565 filed Apr. 30, 1991 (now U.S. Pat. No. 5,152,150) which was a continuation of application Ser. No. 581,676 filed Sep. 13, 1990 (now abandoned) which was a continuation of Ser. No. 795,568 filed Aug. 18, 1989 (now abandoned).

This invention relates to health care and especially to prevention of the ingestion of toxic organic carcinogens. More particularly, the invention relates to method for the removal of volatile toxic organic carcinogens from drinking water. The invention contemplates the use of standard conventional equipment for carrying out the methods whereby removal can be effected simply and inexpensively at home with water from the tap or with water from commercially purchased bottled water.

FIG. 1 is an elevational view partially in section illustrating an especially designed cap; and

FIGS. 2, 3, and 4 are flow type diagrams illustrating equipment for practicing the invention.

The portable water in the United States has been increasing in organic pollutants since the early fifties. The Environmental Protection Agency was formed in 1972 and they have found several hundred toxic organics in our drinking water, which are called TTOs or total toxic organics. Many companies have tried to make purifiers for the home owners to remove various pollutants.

Ion exchange units were introduced on the market, but only removed metals. The systems were beneficial with respect to removal of sodium for heart patients but at the same time removed calcium which is essential to good health. Another alarming attribute was that if ion exchange resin was swallowed, it could cause liver cancer and the resin did nothing for the removal of the TTOs, which are considered the most important aspect of the problem.

Charcoal will absorb the toxic organics, but the removal capacity is so limited that the unit must be kept off the main stream of the water and used only for drinking water. This criteria is also the downfall of such a system. I have found that a charcoal unit guaranteed for five years gave off more TTOs than it removed after six months of operation.

For illustration, the incoming stream contained 2 parts per billion (ppb) of methylene chloride, 1 ppb of trichlorethylene and 3 ppb of chloroform. After going through the charcoal and very fine filter, the answer was surprising.

    ______________________________________                                         Methylene chloride  6.3 parts per billion                                      Trichloroethylene (TCE)                                                                            2.7 parts per billion                                      Chloroform          4.5 parts per billion                                      ______________________________________                                    

A good quality filter was used to stop any possible fragments of charcoal getting through. The instrument to measure these toxic organics is a GC/MS, which stands for gas chromatograph with mass spectroscopy detection. Various other detectors can be used in place of the mass spectroscopy. The normal sensitivity is 0.5 parts per billion for the chlorinated compounds.

The above tests were tried under varying conditions and it seemed the charcoal loaded up very quickly. A scientist in Washington wrote an article on this phenomenon, which he called the wave effect. Even if the carbon was not saturated, the idle water surrounding the absorbing bed would become saturated with the various pollutants. When flushed the water that was supposed to be safe, was now more polluted than the original. Flushing for one minute or maybe two minutes might clear the charcoal bed, but who wants to play Russian roulette with cancer.

People want a positive answer when it comes to removal of cancer causing agents or carcinogens from their drinking water. Taking a quart or two from an ordinary tap and boiling the water will remove the volatile compounds, such as methylene chloride, TCE and chloroform. Unfortunately, the water tastes bad, the process uses energy and the process is awkward and time consuming.

I have found a simpler way to remove the pollutants, Add 11/2 quarts of tap water to a glass jar so that it is 3/4 full and leave it out overnight on the counter so that the water assumes the room temperature. Tap the bottle and screw the cap on tightly and place in the refrigerator for at least eight hours. The drop in temperature will cause a vacuum in the glass bottle and pull the carcinogens out of the water. Heating the glass bottle slightly (150° F.) will create a better vacuum. The foregoing may be accomplished by any conventional method.

Illustration 1

    ______________________________________                                         Boston tap water                                                                             4.5 ppb     TCE                                                  After vacuum  not detected                                                                               (less than .5 ppb)                                   Philadelphia tap water                                                                        30 ppb     chloroform                                                           6 ppb     methylene chloride                                                 1.4 ppb     TCE                                                  After vacuum  not detected                                                                               (less than .5 ppb)                                   Orlando, FL tap water                                                                        3.1 ppb     TCE                                                                1.8 ppb     chloroform                                           After vacuum  not detected                                                                               (less than .5 ppb)                                   ______________________________________                                    

Illustration 2

I gave the instructions to a local water company. After several days they called and said the process did not work. Further investigation revealed that they pulled a vacuum with a pump for only ten minutes and the results were

    ______________________________________                                         Water company      2.1 ppb   chloroform                                        After vacuum (10 Min.)                                                                            2.0 ppb                                                     ______________________________________                                    

After trying many combinations, it appeared that five hours were needed to bring the chloroform down to the detection limit.

    ______________________________________                                         Water company sample                                                                              2.1 ppb   chloroform                                        After vacuum        .5 ppb   chloroform                                        ______________________________________                                    

It appears that it is important to lower temperature and pressure together and slowly.

    ______________________________________                                         Water company sample                                                                            35° F.                                                                            2.1 chloroform                                      After vacuum 8 hours                                                                            35° F.                                                                            No detection                                        ______________________________________                                    

Some research was devoted to placing a vacuum pump in a refrigerator and this proved successful but very expensive. A bottle and vacuum gauge would be less than $25.00 whereas a vacuum pump would be over $500.00. On a mass production basis the costs would be greatly reduced and the TTOs vented outside the refrigerator.

In recent months I have asked a number of people to try a set of bottles with vacuum gauge and without it. They definitely wanted the vacuum gauge. It was found the sealing ability of the screw caps was soon lost and the possibility of preventing cancer by the removal of the carcinogens was too important to fool with. A positive measure of the vacuum in the bottle was essential.

The problem of losing the vacuum after 20-30 turns was solved by using a specially designed cap. While I am not ruling out the possibility of using metal caps, it appeared likely a plastic cap would hold up for 1000 openings and closings. These was less chance of an off-taste with plastic caps. Many testers remarked that the water tasted better than bottled water.

This prompted me to check several different bottled waters.

    ______________________________________                                         BOTTLED WATER NON CARBONATED                                                   ______________________________________                                         Sample A    chloroform      17.4 ppb.                                                      carbon tetrachloride                                                                           2.1 ppb.                                           Sample B    methylene chloride                                                                             3.9 ppb.                                                       toluene         .6 ppb.                                            Sample C    methylene chloride                                                                             4.6 ppb.                                                       bromodichloromethane                                                                           2.1 ppb.                                                       1,1,1-trichloromethane                                                                         1.8 ppb.                                                       chloroform      1.7 ppb.                                           ______________________________________                                    

Pulling a vacuum by cooling in a refrigerator overnight proved to lower all carcinogens below the detection point.

With respect to the above mentioned specially designed cap, a typical cap is illustrated in FIG. 1. The cap has a body 1 lower internal threads 2, a cavity 3 designed to accept the tops of the neck of a water bottle or container, a neck 4 having internal threads 5 and opening 6. The neck 4 and threads 5 constitute a fitting 7 to which can be attached the stem of vacuum gauge on a vacuum pump.

The annular lip 8 extends down into the bottle or container and when the cap or cover is tightened down it measurably enhances the seal.

The container referred to above can be formed from glass or plastic provided the material has the rigidity to withstand vacuum. If cap is to be molded from plastic I prefer polypropylene.

It will be appreciated that a vacuum gauge or a vacuum pump can easily secured to the fitting 7. Naturally, the fitting can be plugged up in the event a vacuum gauge is not desired and/or the vacuum is not to be created by a pump.

I have referred to the components for removing the pollutants as conventional and standard. This is true of the GC/MS equipment even though this equipment is not ordinarily available in a dwelling. With respect to GC/MS equipment it is contemplated that the container for water and it's cap or cover be precalibrated.

If the container and cap are to be used with a vacuum pump, information on the vacuum level and the time under vacuum for desired removal are provided. Normally this will be 6-7 inches of mercury held for about 8 hours.

If the container (with cap or cover) is to be set up in a refrigerator for the vacuum creation, information on the desired refrigerator temperature and the time to be spent in the refrigerator for desired removal are provided.

With respect to time and temperature the following chart will provide a guide.

    ______________________________________                                         Inches of Mercury                                                                              Time(hours)                                                                               Temp(°F.)                                    ______________________________________                                         4               48         35                                                  5               24         35                                                  6               10         35                                                  7                8         35                                                  ______________________________________                                    

With respect to the testing time period with GC/MS equipment the following is to be noted.

When a container is taken from the refrigerator and a sample removed and tested in the GC/MS equipment it will be necessary to return the container to the refrigerator if the reading is more than 1/2 part per billion. Before returning the container to the refrigerator, water should assume room temperature. This may be done by leaving the container out of the refrigerator overnight.

With the methods herein note that the volatile pollutants in the space above the water are dispersed into the atmosphere when the container cover is removed. This is not detrimental in as much as the density in the atmosphere is negligible as compared to the density in the water.

As will be understood, the above described arrangements for drawing a vacuum by a pump each contemplate (like the version of drawing the vacuum by refrigeration) that water be obtained from the container by removing the cap.

In the event it is desired to obtain water via a spigot on the bottom of the container, a valve should be secured to the cap (say fitting 7) which can be activated to open the space above the water in the container to the atmosphere and thereby break the vacuum. After the water is drawn off, the valve can be activated to seal the space and permit the vacuum to again be created.

The valve and the spigot can be operated in coordination with one another, either manually or automatically.

In connection with the spigot/valve arrangement. I want to point out that there are vacuum pumps now available which can draw vacuums up to 30 in. of mercury and which are of a size and cost making same feasible to be used in my method. These pumps provide an additional advantage in that the same can be employed to purge the carcinogens in the space above the water. For such purposes, a needle valve is provided on the bottom of the container (near the spigot) which when opened will allow air to be pushed up thru the water and bubble out into the space. In the meantime the vacuum pump is activated to begin to evacuate the space. The foregoing is done over a short period of time and the needle valve closed and the vacuum pump stopped. The valve in the cap and the spigot both can be opened and water drawn off.

It will be understood that the just described spigot and valve arrangement can be employed in a refrigerator.

Further, it will be self-evident that automatic means can be provided for filling the container and light means can be employed with a vacuum gauge to indicate or alert that the desired vacuum has been reached.

In FIGS. 2, 3, and 4 I have provided sketches diagrammatically illustrating equipment for practicing the inventions as defined in claims 1-6.

In FIG. 1, the container 10 has a screw-on cover 11 with a fitting 12. The standard vacuum pump 13 has a fitting 14. The fittings 12 and 14 are connected by line 15.

The GC/MS equipment is indicated at 16 and has a port 17 into which water from the container 10 can be poured.

In FIG. 3, the container 20 has a screw on cover 21. A value 22 is connected to the top interior of the container and has a fitting 23. The valve 22 is adapted to connect the interior of the container 20 either to the atmosphere or to fitting 23. The vacuum pump has a fitting 25. The fitting 23 and the fitting 25 can be connected by a line indicated by the dotted line 26.

Near the top, the container has a spigot 30 thru which water in the container can be emptied. Near the bottom the container has a controllable needle valve 31 (manually operated) in conjunction with the vacuum pump 24.

FIG. 4 illustrates a refrigerator 32, having doors 33 hinged at 34 and door opening handles 35.

The refrigerator is large enough to receive the container mentioned in connection with FIGS. 2 and 3.

I will now explain a simplified method for attaining the objectives of the invention.

Preferably, this is done by using an extra thick plastic bottle, filling with hot steaming water, tightly closing the bottle, allowing it to cool down in a room temperature environment for approximately two hours, and then placing in a refrigerator, such as a household refrigerator, and allow to cool for at least five hours. Usually, the bottle remains in the refrigerator overnight.

Hot steaming water has a temperature of substantially between 160°-200° F. At that temperature range, steam vapor rises from the surface.

As indicated heretofore, a household refrigerator will have a temperature range between 32° F. and 40° F.

The bottle or container must be constructed, when closed, to sustain an internal vacuum and to withstand the temperature range of hot steaming water. I have used high density polyethylene as the plastic material with a wall thickness in the side, bottom, and pouring throat of approximately 1/8 inch. This provides the necessary strength to prevent collapse under internal vacuum. A thicker wall may be used if desired.

The bottle or container is conveniently in the shape of a one gallon plastic milk bottle with the wall thickness as above indicated.

Normally, glass cannot be used as it would eventually fracture under thermal shock and if dropped on a hard surface when under vacuum it would blow up like a bomb.

I want to point out that the step of allowing the partially filled bottle to cool down in a room temperature environment can be eliminated and the bottle placed directly in the refrigerator.

The advantage of the two step method is that there is a saving in energy which is very important to the national energy saving programs. Also, the two step method is preferred because I believe more of the carcinogens are removed than in the one step method. 

I claim:
 1. The method of removing volatile toxic organic substances from drinking water comprising the steps of:providing a container which can be opened and closed, which has fitting means for connecting the interior of the container to a vacuum pump and which is constructed, when closed, to contain water and to sustain an internal vacuum; providing drinking water and opening said container and partially filling the container so there is an open space with said fitting in communication with the open space; providing a standard vacuum pump which can create a vacuum; closing said container and connecting said fitting to said vacuum pump; and operating said vacuum pump for a period of time to create a vacuum in said space so that volatile toxic organic substances in said drinking water exit from the drinking water and enter said space.
 2. The method of claim 1 wherein said period of time is determined by:providing GC/MS equipment; stopping said vacuum creation and removing a quantity of water from the container and testing in said GC/MS equipment, to determine whether the quantity of any organic substance in the drinking water is more than 1/2 part per billion; and if the quantity of any organic substance in the drinking water is more than 1/2 part per billion continuing said vacuum creation and subsequently repeating said test.
 3. The method of removing volatile toxic organic substances from drinking water comprising the steps of:providing a container which can be opened and closed, which has fitting means for connecting the interior of the container to a vacuum pump and which is constructed, when closed, to contain water and to sustain an internal vacuum; providing for the fitting to have valve means connected thereto operable to connect the space above the water in the container to the atmosphere or to seal off the space; providing drinking water and opening said container and partially filling the container so there is an open space with said fitting in communication with the open space; providing a standard vacuum pump which can create a vacuum; closing said container and connecting said fitting to said vacuum pump; operating said vacuum pump for a period of time to create a vacuum in said space so that volatile toxic organic substances in said drinking water exit from the drinking water and enter said space; and providing for the container to have spigot means to pass water from the interior to the exterior when the valve means has connected the space above the water in the atmosphere.
 4. The method of claim 3 wherein there is further provided a needle valve below the surface of the water and the needle valve and the vacuum pump are operated so that the needle valve connects the water to atmosphere and when the same bubbles up thru the water the vacuum pump is operated to start to evacuate the space above the water.
 5. The method of claim 3 further including:the step of providing refrigeration means with an internal temperature between 32° F. and 40° F.; and the step of placing said container in said refrigerator, and connected to said vacuum pump.
 6. The method of claim 4 further including:the step of providing refrigeration means with an internal temperature between 32° F. and 40° F.; and the step of placing said container in said refrigerator, and connected to said vacuum pump. 